Why do we celebrate Halloween by putting on bizarre outfits and asking strangers for candy? Who is Stingy Jack, and why does he haunt our dreams? We decided to take a look at a few of Halloween's most well-known customs and ask, What do they all mean?

The next time you think it would be funny to scare the living daylights out of someone, you might want to consider this: medical experts say that an intense fright can severely stun the heart, enough even to kill a perfectly healthy human being.